1. Field of the Invention
The present invention relates to a method for gesture-controlled opening of an actuating element in a motor vehicle. The invention also relates to an associated actuating device. The actuating element to be opened is, in particular, an automatically movable trunk lid or an automatically operable sliding side door of a motor vehicle. As a general rule, however, the invention can also be applied to other actuating elements with which openings in the body shell of a motor vehicle can be opened in a motorized manner, for example a motorized sunroof or a motorized convertible top. Such actuating elements to be opened are referred to below as a “closing element.”
2. Description of the Background Art
Use of gesture-controlled actuating devices for automatically moving motor vehicle trunk lids is a recent development. With such an actuating device, the vehicle user produces an open command by executing a defined gesture, in particular a certain hand or foot movement, in the vicinity of the closing element. The actuating device senses the vehicle user's gesture by means of a proximity sensor and, by analyzing the sensor signals, checks whether the sensed gesture matches specific criteria stored for an open command. In the event that the actuating device recognizes the request for opening, it initiates opening of the closing element, which is to say opening of the trunk lid, for example. Gesture detection primarily employs capacitive proximity sensors, which detect the approach of the command-issuing body part in a contactless manner.
It is a disadvantage, however, that such a gesture-controlled actuating device is relatively susceptible to interference events that are not based on a genuine opening request by the vehicle user, and that often are not even elicited by a gesture on the part of the vehicle user. For example, such interference events can be produced by splashing water or by an inanimate object approaching the sensor of the actuating device, in particular by the wash water and/or the brushes of a car wash. Under such circumstances, opening of the closing elements must be avoided in order to prevent damage to the vehicle.
In order to prevent erroneous opening of a gesture-controlled trunk lid, sometimes the sensor signals of a gesture-controlled trunk lid actuating device are tested for plausibility, with the actuating device only opening the trunk lid when the sensor signals are recognized as “plausible” based on predefined criteria. “Plausibility” is present here when the sensor signals correspond to predefined expected values for ordinary, appropriate user behavior. For example, an actuating device provided for moving a motor vehicle trunk lid suppresses opening of the trunk lid when it detects multiple successive events in the sensor signal within a few seconds indicating an open command. Such a sensor signal is classified as “implausible” here because under normal operating conditions it is not to be expected that a vehicle user will want to open the trunk lid multiple times in such a short period of time. However, such a plausibility test cannot prevent erroneous opening of the trunk lid under all imaginable circumstances.